Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 02 May 2016 21:07:05 +0000
From:      bugzilla-noreply@freebsd.org
To:        freebsd-bugs@FreeBSD.org
Subject:   [Bug 209202] [PATCH] [powermac_thermal] In-Kernel PowerMac fan control does not effectively regulate some quad core models
Message-ID:  <bug-209202-8-XHb7ccaC5G@https.bugs.freebsd.org/bugzilla/>
In-Reply-To: <bug-209202-8@https.bugs.freebsd.org/bugzilla/>
References:  <bug-209202-8@https.bugs.freebsd.org/bugzilla/>

next in thread | previous in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D209202

--- Comment #3 from gmbroome@vcu.edu ---
(In reply to Mark Millard from comment #2)

The history on my work with this is that I grabbed two of these systems on =
the
cheap from "the Bay."

Both had the "revision 2" CPU assembly, and both worked fine w/ OS X, Linux,
and FreeBSD.

Six months on, one of the cooling pumps in a system died.  The only replace=
ment
that I could get was a "revision 1" CPU assembly.  After doing the replacem=
ent,
both OS X and Linux continued to work fine (albeit with the same reduced
performance that you noted) but FreeBSD showed the precise behavior that you
described in the mailing list posts.

Through a series of CPU assembly swaps, and ordering a second r.1 purely for
the testing, I'm reasonably certain that the r.1 CPU assembly is, itself, t=
he
culprit.  Though I certainly understand the notion that installing
known-defective hardware (why else would there have been a rev?) will cause
problems, it makes sense to go ahead and accommodate this r.1 CPU assembly =
in
the driver as the r.1 CPU assembly is the far more common replacement part
these days, and r.2 is getting very difficult to obtain, even if one has
bottomless pockets.  Based on my own testing, the provided patch allows the=
 r.1
assemblies to work, and has a negligible impact on r.2 assemblies.

--=20
You are receiving this mail because:
You are the assignee for the bug.=



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-209202-8-XHb7ccaC5G>